Lots of friends have suggested me to start using Sublime Text instead of Notepad++, but I've been happy so far with Notepad++. I use Notepad++ mainly for quick editing files (Haskell, Python, C#, HTML, JS, CSS, etc.), copying & paste pieces of text and running macros on it, etc.
What are the main differences in the feature set of Sublime Text and Notepad++?
One thing that should be considered is licensing.
Notepad++ is free (as in speech and as in beer) for perpetual use, released under the GPL license, whereas Sublime Text 2 requires a license.
To quote the Sublime Text 2 website:
..a license must be purchased for continued use. There is currently no enforced time limit for the evaluation.
The same is now true of Sublime Text 3, and a paid upgrade will be needed for future versions.
Upgrade Policy A license is valid for Sublime Text 3, and includes all point updates, as well as access to prior versions (e.g., Sublime Text 2). Future major versions, such as Sublime Text 4, will be a paid upgrade.
This licensing requirement is still correct as of Dec 2019.